The gallbladder is a small, pear-shaped organ in which bile produced by the liver is stored. Over time the stored bile (composed of water, cholesterol, fats and natural salty detergents) becomes increasingly concentrated in order to better break down and absorb fats during digestion.

Gallstones, or cholelithiases, are the tiny deposits of salts and cholesterol that can form if there’s a chemical imbalance in the gallbladder, often due to an excess of cholesterol in the bile.

The ‘stones’ range in scale from tiny granular crystals to the size of a golf ball. Though they’re usually formed in the gallbladder – and small stones cause no symptoms or pain whatsoever – if a large gallstone becomes stuck in one of the many bile ducts that connect the gallbladder and the duodenum (start of the small intestine) a patient can experience great discomfort. If a gallstone blocks the flow of digestive enzymes produced in the pancreas, a condition called pancreatitis can develop, which can cause acute pain.

Ultrasound scans are able to detect gallstones and, if necessary, the entire gallbladder can be removed using keyhole surgery. This generally low-risk procedure is called a laparoscopic cholecystectomy. Shockwave treatment can also be used to shatter the stones in situ, after which they can be passed naturally.